Frame the fabric in any garment photo and take its print, colours and texture into Procreate for your flats.
Sample: indigo denim twill. Drag across the photo to frame a new swatch, drag inside the frame to move it, or drag its corner to resize.
In Procreate: Actions → Add → Insert a photo. Put the layer above your flat's colour layer, tap it and choose Clipping Mask, then pinch to fit the print. The repeat tile is one 2000 px repeat: open it in Photoshop and use Edit → Define Pattern to make it a pattern swatch.
In Procreate: Colours → Palettes → + → New from File and pick the saved image.
A Procreate brush paints one colour at a time, so your fabric comes as a small set, one brush per colour. Paint an area with each brush in order, each in its own colour, and the fabric builds up. The pattern is fixed to the canvas, so the colours line up.
In Procreate, paint with brush 1 in its colour, then brush 2 in its colour over the same area, and so on. Keep each brush's Grain → Scale the same so the layers stay lined up.
When the brush is ready, tap Open in Procreate and choose Procreate. It appears in the Imported set. Or tap Save to Files, then tap the file in the Files app.
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